PIR motion detector for a decorative lantern

Abstract

A small-sized hidden motion detector that can be incorporated in a decorative manner into a decorative lantern. The motion detector can be incorporated into lighting fixture designs not previously amenable to a hidden motion detector in the body of the lighting fixture. A small decorative motion detector housing is provided defining a compact interior region with a PIR sensor mounted inside and providing a sufficient optical pathway for a practical motion detector of wide angular field of view that can nevertheless fit inside commonly found small-sized decorative lantern elements. In one embodiment the motion detector is hidden in a small generally cylindrical decorative element of the sort that is found in a number of traditional decorative lantern designs and that has not previously been amenable to a hidden motion detector. Another embodiment includes a mechanism for mechanically adjusting the range and responsiveness of the motion detector notwithstanding the small size of the space available for housing the detector.

Description

[0001]This application claims the benefit of provisional application No. 60 / 362,753 filed Mar. 7, 2002.BACKGROUND OF THE INVENTION[0002]The present invention relates to passive infrared motion detectors of the type used in residential outdoor lighting fixtures, for example, to illuminate a walkway or driveway when a person or automobile approaches. The invention is more particularly directed to an arrangement for making the motion detector an inconspicuous element of the lighting fixture and to an arrangement for adjusting the motion detector range.[0003]Early passive infra-red motion detectors used for activating outdoor lighting fixtures were big and bulky. They were only used with floodlights or with other non-decorative, primarily utilitarian lighting. The motion detectors of that time were contained in a separate, bulky and conspicuous housing that was unsuitable for use with stylish decorative lanterns commonly mounted in a prominent position by the front door of a house to we...

AI Technical Summary

Benefits of technology

[0009]The present invention provides a motion detector in a decorative lighting fixture, the motion detector being of small size, and particularly of small transverse dimension, which permits the motion detector to be incorporated into lighting fixture designs not previously amenable to a hidden motion detector in the body of the lighting fixture. A small decorative motion detector housing is provided defining a compact interior region with a PIR sensor mounted inside and providing a sufficient optical pathway for a practical motion detector of wide angular field of view that can nevertheless fit inside commonly found small-sized decorative lantern elements. In one embodiment the motion detector is hidden in a small generally cylindrical decorative element of the sort that is found in a number of traditional decorative lantern designs and that has not previously been amenable to a hidden motion detector.

Problems solved by technology

Early passive infra-red motion detectors used for activating outdoor lighting fixtures were big and bulky.

The motion detectors of that time were contained in a separate, bulky and conspicuous housing that was unsuitable for use with stylish decorative lanterns commonly mounted in a prominent position by the front door of a house to welcome visitors.

Only a relatively few of the available lantern styles lend themselves to building in an inconspicuous motion detector.

The presence of the motion detector was nevertheless plainly evident, and some lantern styles could not be used with the backplate-mounted motion detector because a portion of the lantern necessarily extended in front of the motion detector and blocked the motion-detecting action.

While this form of design provided a decorative lantern with integrated motion detector, it could not be incorporated into most of the classic and contemporary lantern styles without interfering with the original style, if it could be incorporated at all.

Despite these developments there still exist a plethora of historic and contemporary decorative lantern styles that are not amenable to a hidden motion detector in the fixture body.

Problems arise when the motion detector is incorporated into the body of the lantern because there is limited space for the optical and electronic elements and because the interior volume available for the motion detector elements may be awkwardly shaped.

The volume of the space to work with and the shape of the decorative exterior fixture walls impose constraints on the technical design of the motion detector.

To add a motion detector to many stylistic lantern designs, it has been necessary either to add a further housing element to the lantern, adversely altering the lantern style, or to place the motion detector on the backplate.

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